IS 12656 : 1969 IS0 1746 : 1983 Indian Standard RUBBER OR Pj_ASTlCS HOSES AND TUBING - BENDING TESTS ( Reaffirmed 2012 ) UDC 621.643.3 : [ 678.4/.8 ] : 620-l 74 @ BIS 1989 BUREAUOF MANAK BHAVAN, INDIAN STANDARDS ZAFAR MARG 9 BAHADUR SHAH NEW DELHI 110002 December 1989 Price Grout3 3 IS 12656 IS0 : 1989 1746 - 1983 Indian Standard RUBBER OR PLASTICS HOSES AND TUBING - BENDING TESTS NATIONAL FOREWORD This Indian Standard, which is identical with is0 1746-1983 *Rubber or plastics hoses and tubing - Bending tests' issued by the International Organization for Standardization ( IS0 ) was adopted by the Bureau of Indian Standards on 21 April 1989, on the recommendation of the Rubber Products Sectional Committee ( PCDC 13 ) and approval of the Petroleum, Coal and Related Products Division Council. Indian Standard IS 443 : 1975 `Methods of sampling and test for rubber hoses ( second revision )`, has already been formulated to prescribe methods of sampling and test for rubber hoses. Reference has been given to IS 443 : 1975 in standards on thermoplastics hoses for a number of tests, such as bore size, lining and cover thickness, and pressure tests. However, there are a number of other methods of tests to which hoses, both rubber and plastics, are being subjected to and are not covered in IS 443 : 1975, Therefore. it has been decided to adopt IS0 test method standards, wherever available. IS 443 : 1975 will be revised in due course to update and align it with international standard to the extent possible. The text of IS0 standard has been approved as suitable for publication as Indian Standard without deviations. Certain conventions are, however not identical to those used in Indian Standards. Attention is particularly drawn to the following: a) Wherever the words `International Standard' appear referring to this standard, they should be read as `Indian Standard'. b) Comma ( , ) has been used as a decimal marker while in Indian Standards, the current practice is to use a point ( . ) as the decimal marker. CROSS REFERENCE In this Indian Standard, the following international standard is referred to. following: International Standard Indian Standard Clause 4 of IS 443 : 1975 Methods of sampling and test for rubber hoses ( second revision ) Read in its place the Degree of Correspondence Technically equivalent IS0 4671 : 1984 Rubber and plastics hose and hose assemblies - Methods of measurement of dimensions The Sectional Committee responsible for the preparation of this standard has reviewed the provisions of the following IS0 standards and has decided that they are acceptable for use in conjunction with this standard: IS0 471 : 1983 Rubber - Standard temperatures, humidities and times for the conditioning and testing of test pieces. IS0 1826 : 1981 Specification. Rubber, vulcanized Time interval between vulcanization and testing - As in the Original Standard, this Page is Intentionally Left Blank 1$12666:1989 1S0 1746-1983 1 Scope and field of application 3.2 3.2.1 Test pieces Typesand dimensions This International Standard sptifiee two methods for the determination of the behaviour of rubber or plastics hoses or tubing when bent to 8 specified radius. Method A is suitable for hoses and tubinQ of bore sizes up to about 60 mm; the size of the apparattta for testing hoses and tubing of larger bore sizes becomes excessive. The method also provides a means of measuring the force required to reach s specified bend radius, and the test may be cerried out at a specified internal pressure. kr method B, the bending characteristics, including the force required for banding, may be determined over a range of temperatures from ­ 60 `C m +200 `C. The nature of the apparatus, however, limits its applicability to hoses and tubing of small bore sizes, i.e. up to about 12,5 mm. The test pieces shall consist either of complete manufactured lan@hs of hose or of suitable test Iengtha. If the manufactured length is shorter than the length required for the test, tes~ piaoee of adequate length (see 3.4) shall be spacialiy manufactured. 3.2.2 Number be tested. Unless otherwise specified, two test pieces shall 3.3 Conditioning of test pieces No test shall be carried out within 24 h of manufacture. For weluations which are intended to be comparable, the test should, as far aapossible, be carried out after the same time interval after manufacture. ISO 1626 shoukf be followed for time between sample manufacture and testing. Sefore testing, test pieces sha}}be conditioned for at taest 16 h 2 References ISO 471, Rubber ­ Standard temperatures, humidifies and times for the conditioning and testii'rgof test pieces. he-interval LSO 1626, Rubber. vulcanized vulcanization and testing ­ Specification. between at a standard laboratory temperature and humidity (see ISO 471); this ?6 h period maybe pert of the 24 h interval after manufacture. 1S0 4671, Rubber and pfxtics hose and hose assembfir?s­ Methods of n?eesurements of dhetwiorrs. 1} 3.4 Procedure Determine the warageexternal diameter 1) of the hose by meansof a suitable mesttring instrument as specifii in 3.1 Apparatus 1s04671. Draw two paralleland diametrically opposed lines along the length of the hose. If the hose has natural curvature, one of the lines shall be on the outside of the curve. On each of these lines, mark a d~tance of 1,6C + 2D or 200 mm vdichever is the longer, where C is twice the minimum bend radius specified specification, so that ttre marked dtiances in the appropriate areexactly opposed, TM willensure a su~fciantdength for the support of the hose. bend teat andadequate The apparatus consists of two guides A and B, guide A being fixed in a plane and guide B being movable in that plane, parallel to, and in line with, guide A (see fiiure 2). {f it is desired to measure the force required to attain the specified radiu~ of curvature, this maybe done,for zxample, by means of a system of pulleys and weights (see figure 11. Care slmuld be taken to minimize the effect of frictional resistance. 1} At present at the stage of drdt. 3 IS 12656 IS0 1746 : 1989 - 1983 Separate 1,6C the guides A and 6 to a distance Place the hose between slightly less than Before testing, environmental peratura test pieces shall be conditioned to their natural curvature (4.1.3) at the chamber in the straight for 5 h in the test tem- + 2D. the guides so that the condition or conforming (see 4.4). ends of the marked distances are parallel to the ends of the guides and remain in this position while the guides are closed to a distance of C + 20 (see figure 2). specified 4.4 Check that the hose on each side is supported to a length of not less than D. Measure the hose outside dimension, T, at any point in the curved portion of the hose (see figure 3). Test temperature will be specified in the appropriate hose The test temperature specification. 4.5 Procedure Measure the external diameter D at the mid-point condition instrument as specified in IS0 4671. of the 4.5.1 4 4.1 4.1.1 Methad 6 test pieces in the unstressed measuring by means of a suitable Apparatus 4.5.2 Compression testing machine, with a rate of travel of provided with a divisions, is atto be from a 4.53 Start the machine and determine the force required to Install the test pieces between the holders with a large the end if any. bend radius and the ends of the test pieces against tops. The curvature shall follow the natural curvature the moving tached jaw of 100 mm/min, A scale, graduated preferably, this preferably in millimetre may be chart recorder. measured graphical or, to the moving jaw to enable the bend diameter determined record. reach the specified NOTES bend radius. 4.1.2 Pair of twin channel shaped holders, fitted with end stops for the hose test pieces (see figure 4). 1 It is advantageous if the machine can be pre-set to stop when twice the specified bend radius C has been reached. 2 The force value obtained by direct reading or from a graphical record should be divided by two to obtain the bending force for a single 4.1.3 Thermostatically controlled environmental chamtest piece. ber, which can be fitted to the testing machine, for access to enable the external measured. diameter with provision 4.5.4 Measure the hose outside dimension, of the hose to be T, at any pornt in the curved portion of the hose. 4.2 Test pieces 5 Expression of results A and method deformation B, calculate the value 4.2.1 Types and dimensions For both method with the permitted specification. T/D hose using the mean value obtained. The value should be compared given in the appropriate The test shall be carried out on two pieces, of equal length, of the hose or tubing be 2G under test. The length of the test pieces depends on the dimensions of the test piece holders and shall bend radius specified + 0,57tC, where G is the length of the test piece holders specification. In no case shall the test pieces (see figure 4) and C is twice the minimum in the appropriate 6 Test report information Standard come into contact with the walls of the chamber and the length L shall always be less than the length of the enclosure. The test report shall include the following a) a reference used to this International : and the method 4.2.2 Number specified, three sets of tests should be carried ; bl a full description of the hose or tubing tested and a reference to the hose specification in accordance with which the hose was tested; c) d) the test temperature; the interna! pressure at which the test was carried out; observations on any abrupt change(s) caused by kinking; in hose section or Unless otherwise out. 4.3 Conditioning of test pieces e) No tests shall be carried out within 24 h of manufacture. For evaluations which are intended IS0 to be comparable, the test for time irregularity f) in curvature the value for D, T, and TID; whether the force 9 deformation; soecified bending should, as'far as possible, be carried out after the same time interval after manufacture. between 1826 should be followed and testing. sample manufacture g) h) T/D is within the permitted required to reach the radius, if appropriate. 4 IS 12666 : 1999 IS0 1746 - 1983 A-A Figure 1 - Method A - Arrangement for measuring bending force Guide A - -Guide I3 --Lb 0 - -__-_----9 h i Figure 2 - Schematic arrangement for method A Figure 3 - Measurement of coefficient of deformation IS 12656 : 1989 IS0 1746 - 1983 Figure 4 - Schematic arrangement for method B 6 Bureau of Indian Standards BIS is a statutory promote certification Copyright 8IS has the copyright any form without grade designations. Revision of Indian of all its publications. No part of these publications may be reproduced in in writing of BIS. This does not preclude the free use, in and sizes, type or BIS. be addressed to the Director (Publications), institution established under the Bureau of Indian activities matters in the country. Srandards Act, 1986 to harmonious development of the of standardization, marking and quality of goods and attending to connected the prior permission the course of implementing the standard, of necessary details, such as symbols Enquiries relating to copyright Standards periodically Indian Standards are reviewed are and revised, when necessary and amendments, Indian Standards should ascertain Comments on this Indian Standard if any, issued from time to time. Users of that they are in may be sent possession of the latest amendments or edition. to BIS giving the following Doc:No. PCDC13(1003) reference : Amendments Issued Since Publication Amend No. Date 0% lsssue Text Affected BUREAU Headquarters : OF INDIAN STANDARDS Manak Bhava(n, 9 Bahadur Shah Zafar Marg, New Delhi 110002 Telephones : 331 01 31, 331 13 75 i: `1, Telegrams : Manaksanstha (Common to all Offices) Telephone 331 01 31 I 331 1375 Regional Offices : Central : Manak Bhavan, 9 Bahadur Shah Zafar Marg NEW DELHI 110002 Eastern : 1 114 C. I. T. Scheme VII M, V. I. P, Road, Maniktola CALCUTTA Northern 700054 Sector 35-C, CHANDIGARH 160036 36 24 99 : SC0 445-446, I r41 2 1843 31641 24 42 Southern : C. I. T. Campus, IV Cross Road, MADRAS 600113 Western : Manakalaya, E9 MIDC, Marol, Andheri BOMBAY 400093 (East) 6 32 92 95 Branches : AHMADABAD. BANGALORE. BHOPAL. BHUBANESHWAR. GUWAHATI. HYDERABAD. JAIPUR. KANPUR. PATNA. TRIVANDRUM. Printed at Printograph, Delhi. India